I am currently working on a hybrid trailer to pull behind my RV to carry my motorbike. The base of the trailer is going to be a basic rectangle approximately 85" X 40" made from hot formed box section carrying a 600lbs bike on a central formed channel. My problem is I'm not sure what size material to use. My first thoughts were for 1" X 2" box but I would like to save weight and money by using 3/4" X 1 3/4" do you think this will be suitable ?
Obviously a lot will depend on where I fit the suspension cross braces etc, but does anyone know a simple formula for working out the strengths of material I will require ?
Thanks, Graeme.

If you are unsure of materials to use for something then the best thing to do is look at what is commercially available for sale and copy it. Go to your local trailer supply place and look at one. You are far from the first person to make a motorcycle trailer.
smith out

What do you mean by "hybrid trailer"? A dual purpose cargo/camper trailer? I started typing "hybrid trailer" in Google and it brought up "hybrid trailer forum" with quite a few different returns. Maybe they can be more helpful.

I would also search for plans to see if someone has done this before. I have been wanting to get/build a teardrop camper, and have been amazed by the completeness of the plans available, some even with endorsements from various state DOT's... FOR FREE!

Phil

maybe should have chosen my words a little better, forgot what you guys call trailers, we call caravans, two countries separated by a common language eh ! My trailer design is different to most things on the market, so it's not gonna be too easy to copy and hopefully I will go into production with them, so I need to work out some stresses etc for wheel and hitch positions as I dont want to be on the end of any law suits.
The design will have to be down to experience, if it looks right and suck it and see principle then, plus a bit of onroad testing by myself and friends.

If you give more details of what you are thinking of and your location we could help you better.

maybe should have chosen my words a little better, forgot what you guys call trailers, we call caravans,

We call them trailers (for cargo, vehicles etc), campers (for well camping and housing), and the caravan is a Dodge,Chevy, or Ford minivan. So as you can see, posting your location in your profile clears up a lot of the language problem as we translate to your location. (grin)

Lincoln Electric has a series of project books that include several sets of plans for various types of trailers: https://ssl.lincolnelectric.com/lincoln/apdirect/store.asp?PID=16&cat=8

Thanks for the replies. As you can see I've ammended my profile to show my location, Cumbria, UK, close to the border with Scotland.
I'm stuck at home at the mo' with a chest infection so have been checking out other designs on the net and have had a bit of a rethink regarding the design and am currently drawing up a few ideas/mods so your comments are spurring me on, thanks.
David, some of those books look to be a good source of knowledge, thanks for the link.

there are engineered plans out there. the link is to a book I have they sell a volume 1 as well it helped me make my trailer for hauling iron work.


http://www.amazon.com/Trailers-How-Design-Build-Structure/dp/0914483323/ref=sr_1_1?s=books&ie=UTF8&qid=1327085804&sr=1-1


http://www.utilitytrailerkit.com/?gclid=CL_W-aij360CFUHc4Aoden7XmQ

It is worth noting that almost all industrially made trailers are made from C section or angle iron . box is strong but because it has an inside surface galvanising and or painting can be a problem. hope that is of help.

Box is useful in the right situation, I had/have an all expanding trailer that I use for all sorts of jobs,

basically it is a 6 X 4 flatbed of 3/4" marine ply on a frame,

the frame is box and expands with sliding box sections to a trailer that is 22 feet long X 8 feet wide, maximum size to two on the road behind a light vehicle here in the UK,

The axle can be slid back to adjust point of balance.

Has caused some amusement and bewilderment over a long period of time.